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KYRA PHILLIPS, CNN ANCHOR: This was a natural occurrence, Niagara-Mohawk power grid overloading, New York communicating with Canada right now trying to get the power back on, the mayor saying possibly within a few hours. John King out of Washington, D.C. with a statement I understand from homeland security - John.

JOHN KING, CNN ANCHOR: The statement from the Department of Homeland Security, Kyra, also information from a number of other federal agencies, obviously they are trying to get a handle on this situation.

All indications are at least no evidence yet of any terrorist attack and most federal agencies telling us they do not believe in any way that this is a terrorist attack. First, the statement from the Department of Homeland Security:

"The department is working with state and local officials and the energy sector to determine the cause of the outage as well as what response measures may need to be taken. We encourage all of those who may be affected to listen and heed the advice of their local authorities."

Now, President Bush, we are told, is being updated constantly. He is on the West Coast on a fundraising trip, one senior official at the White House saying that they have "absolutely no evidence or indication that this has anything to do with terrorism at all."

They, of course, will not rule it out until they have definitive answers. They are looking for more information but another official at the Homeland Security Department and at the White House telling me that there are not the meetings you would see underway in normal circumstances in such a case.

And so, the government at this point trying to get all of the information possible but every indication, Kyra, is that this is not terrorism that it is, as you say, the natural occurrence - Kyra.

PHILLIPS: All right, our John King with that statement from the Department of Homeland Security, a bit of good news within quite a bit of a chaotic time. You're seeing the pictures here via WCBS out of New York.

If you are just tuning in a massive blackout that's hit New York City, also Detroit, Michigan, Cleveland, Ohio, Toronto and Ottawa all due to the Niagara-Mohawk power grid being overloaded.

As our John King was saying, also Mayor Michael Bloomberg, the Mayor of New York City, most likely a natural occurrence not an act of terrorism, the mayor also saying hopefully within a few hours this power will get turned or get jumpstarted and get back on.

The Office of Emergency Management in the process of attending to hospitals and underground transportation and getting to people, evacuating them, and treating them as necessary.

Now, Patty Davis joins us from Washington, D.C. Also, I am told all three airports coming to a ground stop. Patty, what else can you tell us?

PATTY DAVIS, CNN CORRESPONDENT: That's right. The Department of Transportation telling us that all three New York City airports, that would be JFK, LaGuardia, and Newark have ground stop programs in effect, meaning flights are grounded at this point.

Now, the FAA says that air traffic control is not the problem. The air traffic control has backup systems. The problem, though, is that the airports, a lot of those airports have backup system only for their priority functions.

And, you know, one of the things that you have to have power for is to run those TSA screening machines, the Transportation Security Administration saying that it has now stopped screening at Newark Airport at the very least. We don't know about the other airports.

That means at this point flights can't take off because there are no passengers that are able to get down to the gate. So, at this point, we do know of ground stops at all three New York City airports. We are also told a ground stop in effect at Toronto as well because of this blackout hitting these cities - Kyra.

PHILLIPS: Patty Davis, we appreciate that. Thank you. We'll ask you to stand by also and bring us more information. Patty just reporting all airports, JFK, LaGuardia, and Newark no flights coming in and out of those airports right now as this blackout continues in New York City. Also Toronto, Patty mentioned, no flights coming in and out of Toronto.

If you're just tuning in those blackouts, once again, New York City; Detroit, Michigan; Cleveland, Ohio; Toronto, Ottawa, also parts of Toledo, we will continue to check in and update you as things change in each one of these areas. Still not quite sure what caused this massive power outage in all these different areas.

Here's a look at sort of how the Niagara-Mohawk power grid works. This is the power grid that was overloaded causing these blackouts. Why it became overloaded still not able to confirm that but the good news is so far Mayor Mike Bloomberg, also our John King, reading to us a statement from the Department of Homeland Security telling us so far not an act of terrorism.

On the streets in Manhattan where thousands of people are trying to figure out what is going on and what they should do next, the mayor saying, asking everybody just to head home and wait for further direction.

Our Bill Hemmer on the streets, Bill can you describe to us where you are, what you see, and sort of the feel for how people are handling the situation right now?

BILL HEMMER, CNN CORRESPONDENT: Yes, Kyra, a few sirens coming down Fifth Avenue. I'm in the lower part of Manhattan right now and I'm watching, literally, bus boys carry loads and loads of ice into neighboring restaurants.

There's a door man at a major intersection literally directing traffic in the middle of a stoplight that is obviously not functioning correctly. It looks like it's completely out at this point.

I think when you had that interview with the mayor he said it quite well. The thing that is quite surprising about the atmosphere here is that things are relatively calm. Yes, the sidewalks are crowded but I have to tell you it's a bit past five o'clock here. You know, it's rush hour in Manhattan. The streets, at least in this part of the city, are not nearly as crowded as they are normally; having said that, the sidewalks do continue to get more and more crowded as people start to flow out of these buildings.

All this went down, Kyra, I think it was about 4:15 Eastern, which would have put us about 50 minutes ago. I was inside walking into a gym actually in Lower Manhattan and, as soon as I walked in, the place went absolutely pitch black and they cleared it out.

I think initially when everyone was cleared out of those buildings in Manhattan there was a lot of confusion but no hysteria by any stretch of the imagination. Walking past a few restaurants you had literally food cooking on the grill and they were stopped in mid cook.

A lot of people were essentially shutting down their stores and their offices and just coming out of the buildings to find out what was happening. One guy pulled over, had his car door open and all of his windows down with the local radio station on trying to let people know what was happening.

It's going to be a long commute tonight for a lot of people by foot. A woman stopped me about 30 minutes ago and said how do I get to Brooklyn from here and I told her go east and it's going to be a long walk for her tonight.

There was a local report, Kyra, about 20 minutes ago on the radio that said traffic near the Brooklyn Bridge was already starting to back up and one could assume that's probably going to be the picture all throughout the five boroughs in New York as we see it now.

It's a warm day, Kyra. I want to point that out again. It's expected to get well over 90 degrees today and the reason I think that's important, although we have no conclusions or nothing from the Office of Emergency Management or the Mayor's Office as to what's happening; however, it's been a relatively mild summer here in the northeast.

If you compare this summer's heat to last summer we had 30 days over 90 degrees. It was one of the hottest summers in the past ten years here in New York. It's been nowhere near that this year; however, today and going into tomorrow and Saturday we had anticipated temperatures well in excess of 90 degrees and today was just the first big shot of that hot summer weather.

Whether that has anything to do with what's happening in upstate New York we can't say right now but it is definitely a warmer day today than what we've seen recently - Kyra.

PHILLIPS: Our Bill Hemmer on the streets of Manhattan. Bill, thank you so much.

I guess the best news right now is it's still day time there. You can see by this picture via WCBS in New York that people on the freeways, people packed on the sidewalks just trying to get home or figure out, as Bill said some people not even knowing which way is Brooklyn depending on where they are.

Massive power outage in New York City, the transportation systems are down. All the airports are closed. The good news, though, the mayor of New York City, Mayor Michael Bloomberg coming out and saying at this point it looks like a natural occurrence, an overloaded power grid.

The Niagara-Mohawk power grid, a massive power grid that helps funnel electricity to New York City all the way to Canada. And, I'm being told now power outage reported in Erie, Pennsylvania, so now New York City, Detroit, Cleveland, Toronto, Ottawa, parts of Toledo, and now Erie, Pennsylvania, all experiencing a massive blackout right now.

Wolf Blitzer back with us from Washington, D.C., Wolf, you talked with the fire department. What are they telling you?

WOLF BLITZER, CNN ANCHOR: Actually, Kyra, I'm in New York City right now. I've been here all week. I'm here at the CNN Bureau at Penn Plaza in New York City and, obviously, there's no electricity here and there are a lot of people out on the streets as you well know, a lot of people stuck in subways. They're trying to emerge from those subways.

There are a lot of people also stuck including in this high rise building where I am, this tall building, a lot of people in elevators that simply stopped once the power went out. So, there's a lot of problems obviously but so far by all accounts people are handling all this situation rather calmly.

The fire department says they've been swamped, of course, with calls mostly from people who are stuck in elevators. But I have to tell you the cell phones by and large are not working, the cell phones that have become such a staple of course for all of us.

You can't make calls. You can't get calls by and large. There are some exceptions. We are hearing, of course, that all of the airports in this area, as well as Boston, Detroit, as far away as Chicago are being affected mostly because security screening at the airports without the power generators don't seem to be working so that's obviously a serious problem.

Streets are basically shut down because traffic has come to gridlock conditions, at least here in Manhattan and big chunks of Manhattan. People are walking. They're out on the streets. It's a hot day but people are surviving obviously under the conditions.

We do know that the fire department and the police department are working on what they say are emergency generators so they do have power. Hospitals in the area also tell us that they're working on generators. They're only admitting very, very severe emergency cases into the hospitals right now but it's a situation that people are dealing with on a minute-to-minute basis.

If you see the pictures from New York and, obviously, we're not going to be able to get many. It's hard to get pictures out of New York City at this point. If you see the pictures you see people walking up and down the streets trying to make their way home and you'll see eventually thousands, tens of thousands, maybe hundreds of thousands of people trying to cross the bridges from Manhattan into Queens, into Brooklyn, to get out of Manhattan right now.

And, I'm sure similar scenes are unfolding elsewhere in the northeastern part of the United States as well as in Ontario and elsewhere in Canada, this Niagara-Mohawk power grid which really emanates, originates at Niagara Falls, outside of Buffalo New York and southern Ontario, providing so much of the electricity for the northeastern part of the United States as well as Canada. It's an amazing scene I have to tell you, something I haven't seen. I don't think I've ever seen anything like this before - Kyra.

PHILLIPS: All right, Wolf Blitzer thank you so much. We'll ask you to stand by there in New York.

I'm getting as you were telling us about the Niagara-Mohawk power grid, it's a perfect time to remind our viewers that even according to the mayor of New York City that it looks like that is what has happened. That's what's caused this massive blackout in New York City, Detroit, Cleveland, Toronto, Ottawa, Erie, Pennsylvania now and parts of Toledo.

We're told that the Niagara-Mohawk power grid has been overloaded. How did that happen? Most likely a natural occurrence, according to the mayor of New York, not an act of terrorism that also coming from the Department of Homeland Security, our John King working his sources there.

Also, I'm seeing that the FBI, according to the Associated Press, the FBI is now checking into this extraordinary outage but has no immediate information about the cause. Maybe we can get our Mike Brooks on the phone. He used to work with the FBI. He's an analyst and correspondent for us here at CNN. Mike might be able to offer some information with regard to what the FBI is looking into. Meanwhile, Deborah Feyerick, another one of our correspondents based in New York. She's - why don't you, Deb, tell us exactly where you are. I understand it's in the subway system possibly?

DEBORAH FEYERICK, CNN CORRESPONDENT: No, Kyra, we walked down from the bureau which is right near Madison Square Garden. A number of people raced down the stairwell thinking that it was something more serious than a power outage.

Across the street, Madison Square Garden was completely blacked out. We were told by a bus worker that, in fact, that the subways are not moving that people are actually stuck in the subways. The busses are trying to move as normally as possible. They are being told by their bosses that they should keep moving to try to ferry people out.

We saw people lining up outside hardware stores to try to buy flashlights and candles. We saw people who were making their way home, again, nobody really knew. Also, a lot of people standing around cars because there's no information and, as Wolf mentioned, there are no cell phones either. It is very difficult to get any sort of cell phone service.

So, people are lining up at phone booths trying to call home but, again, we are told that people are stuck in the subways but you can see that everybody has sort of left work now and is trying to make their way home as quickly as possible.

You are looking right now it looks like the east side of Manhattan. We can tell you that on the west side of Manhattan the cars seem to be moving pretty well. There are no stoplights, no lights at all but still traffic near the tunnels seems to be moving, at least on the west side.

So, again, that's what we can tell you right now. We walked down. People seem pretty calm. They were trying to get water, things like that, again, no power anywhere.

PHILLIPS: All right, our Deb Feyerick, another one of our correspondents based in New York sort of giving us an inside feel to what's taking place in New York City. If you're joining us, once again, a massive power outage in parts of the United States, right now New York City, Detroit, Cleveland, Toronto, Ottawa, Erie, Pennsylvania, parts of Toledo, all due to the Niagara-Mohawk power grid being overloaded.

Right now, according to the mayor of New York, also a statement from the Department of Homeland Security, our John King not an act of terrorism, nothing to lead officials to believe that this is an act of terrorism at this point, most likely a natural occurrence.

Also with us now on the phone, as you can imagine we have a number of correspondents, employees of CNN in a number of these areas. Dana Bash now, one of our White House correspondents, Dana exactly where are you and give us a feel for what you're experiencing.

DANA BASH, CNN WHITE HOUSE CORRESPONDENT: Hi, Kyra. I am just at the Lincoln Center subway station on 66th between Broadway and Columbus. That's the upper west side.

And I'm standing just at the entrance to the subway station and talking to people really as they come out just about one-by-one and talking about what it's been like, just about an hour down in the subway stuck there really with no power, no air-conditioning, obviously no electricity.

People who are coming out are saying that it's relatively calm but there was sort of an initial sense of panic. People are trying to squeeze out of the subway through in between the cars and making their way up. There are children down there who are scared but essentially people who are - a number of people who have come up have said it's at this point relatively calm.

And, on the streets, just to echo what Deborah and Wolf have said, certainly there are a number of people walking around on the streets but the traffic, interestingly, is running smoothly and it's an amazing sight on Columbus Avenue. There are regular, average New Yorkers, citizens who have taken it upon themselves to be traffic cops.

They're directing traffic and they're really keeping things smoothly. They're definitely not employees of the city but they are doing their civic duty and keeping things running by standing in the street and directing traffic.

But, essentially, it's relatively calm, lots of people out on the street and trying to figure out exactly what is going on. You see people sort of hearing for the first time what's going on and trying to figure out where they're going to go next.

PHILLIPS: All right, out Dana Bash, thank you.

Just supporting the fact as we see these pictures of thousands of people wandering the streets in Manhattan and other parts of New York that even where temperatures are in the 90s right now, it looks like that there are no major signs of panic. People in New York City are remaining calm just trying to figure out how to get home and where exactly they are and how they're going to get there.

Our Jason Carroll and our Bill Hemmer even saying that folks even not quite sure where they were or which direction they should start heading. You get so used to public transportation but right now it's all stopped.

All the airports in New York City, all transportation from railroad to subway, but the best news probably coming from the mayor of New York and also our John King and that was the statement from the Department of Homeland Security. John, you're joining us once again from Washington, D.C. So far, it doesn't look like this is an act of terrorism.

KING: It doesn't look that way, Kyra, but I want to correct the impression that the federal government is ruling that out. No such definitive statement as yet at all. The Department of Homeland Security statement says they are looking into this that they do not know the source and the cause of this and they are urging people to heed the advice of their local authorities, like Mayor Bloomberg, who you spoke to earlier.

As we call around the government we are getting no indications and government agencies are telling us there is no evidence that this is a terrorist attack. They, of course, will not rule that out until they can say definitively what the cause of this power outage in several U.S. cities is.

At the White House, officials say President Bush is being kept up to speed. He is in California along with his chief of staff and his deputy national security adviser. He is being briefed as developments warrant. Here at the White House, officials say they have no information on the source of this.

One senior official though saying there is no evidence, absolutely no evidence, this official said, that there is any terrorism involved, another official saying that there would be a series of urgent meetings involving certain officials if the suspicion was that this was a terror strike and that there is no evidence of those meetings but they will not definitively rule out anything right now because the information is so sketchy.

We want to go now to our Kathleen Hays. She, I understand, is in the financial district of New York. Kathleen, we've received first word of this here a little after four o'clock, right after the markets would have closed. Your assessment of exactly when it impacted the financial district.

KATHLEEN HAYS, CNN CORRESPONDENT: Well, actually, you know I am at the CNN Bureau at 5 Penn Plaza and, in fact, I had just finished a report on the economy, walked off the set and suddenly we were completely without power.

I got on the phone as soon as I could. Of course, you know, four o'clock is when the stock market closes; however, the government bond market, which is about three or four times as big as the stock market, trades virtually 24 hours.

I spoke to Ethan Harris who is the chief economist at Lehman Brothers Securities here in New York. He said the bond market definitely had a reaction. Basically, people buy bonds when there is uncertainty and there was definitely a knee jerk response in the bond market. There was a move in the benchmark ten-year note, a drop in yield.

Quickly, though, it seemed like people headed for home. It was very hard to track down other people. But let's think in terms of the economy impact because certainly there's a short term impact. Just think of every restaurant, movie house, theater, grocery store in New York that's going to have either people who aren't showing up or, you know, (unintelligible) of food that is melting so there is that near term impact. And, in fact, Ethan Harris said think of it at first glance like a snowstorm. When things are shut down there's some economic losses. There's hours lost in terms of hours worked. There's output that isn't there. The question is, of course, if this shortage lasts, if this power grid is not repaired quickly that could have a more lasting impact.

The other thing, of course, even though as John, you just said, government is not going to say this had nothing to do with any kind of terror or sabotage and they know for sure at a time when the economy is doing better, when the stock market is doing better.

Economists - I also spoke to John Sylvio (ph) who's the chief economist for Wachovia in Charlotte, North Carolina. The last thing they're saying is that investors would need is a sense of uncertainty again, a sense of risk.

Of course, everyone's first thought is this a terror attack? If it were to turn out to be some kind of terror incident it probably would have a bit more of an unnerving impact on the financial markets, even on the stock market when it opens again tomorrow.

It will be interesting to watch overnight trading and see how traders are reacting overseas. So far, though, if this is just a brief outage, if things get back to normal, some people are going to take a hit in terms of their business, in terms of their profits but get back to business and put it behind us.

But, I think the question economists will be asking is to what extent again. Even an incident like this does shake people's confidence even if it isn't terror just in their own economy or how can a power grid go out for the whole northeast?

This is not terrorists. This is not London. We're not having the kind of scorching temperatures they're having for the power to go down. This is, think about it, power is what drives every business, you know.

You can't go to work. You can't have a TV network. You can't sell your ads when you don't have power, so it's an unfortunate thing to happen right now and we'll wait to see if it has any more lasting impact - John.

KING: And, Kathleen, you said when the markets open tomorrow, I assume that is everyone's expectation that this will be solved by then but at this hour that is still an if.

HAYS: You're absolutely right it's an if and I can tell you this if the markets aren't open tomorrow that is something that is not good for the stock exchange. It's not good for the New York economy.

That's what John Sylvio pointed out. He said it's going to increase this sense of the businesses who are in Wall Street of needing to have diversification in terms of their location. In fact, he said, hey, this could be good for real estate out in north New Jersey. He said this also could make a lot of traders and investors think about using more of these electronic trading platforms which are not as popular as the floor of the stock exchange but it's the kind of thing that renews that sense that the stock exchange is a physical location that is vulnerable.

And, again, even if it's just a power outage, if the market doesn't open again tomorrow this ripples. This can really, I'm not going to say it's going to bring anybody down or inflict such huge losses but it takes a bite and nobody needs bites taken out of their bottom lines right now.

So, it's interesting then that I'm assuming that things are going to be just fine and back to normal tomorrow and I'm sure that people like Dick Grasso, the President of the NYSE are hoping they're back to normal as well.

KING: Kathleen Hays in New York tracking the economic impact of all this.

There you see a glimpse, we're moving away, this live picture from WNYW, one of our New York affiliates. One of the immediate cultural impacts of a power outage in New York City, a shot of Times Square the big screens up on the wall where tourists and city residents often stop to take a look at the news, take a look at a program on the air, those screens now black because of a power outage in New York City also affecting several other half dozen other cities as well.

Early indications are no terrorist attack but the federal government says it cannot rule that out just yet. Among our correspondents trying to keep track of what the government knows and what it is finding out, our Justice Department Correspondent Kelli Arena - Kelli.

KELLI ARENA, CNN JUSTICE CORRESPONDENT: John, the FBI says that it is looking to determine what the exact cause of the blackout is, whether it's technical or due to what it calls other related activity.

They are not using the "T" word, terrorism, but FBI officials are saying that there were no warnings prior to the blackout so no evidence of any kind that this is terrorism related.

I'm also told by some other government sources that some officials are checking with security and computer experts to see if the worm that emerged on Monday afternoon, the computer worm called Blaster or Love Scan by computer security companies had anything to do with this.

Some experts are saying no. Others are checking into it and saying there may be some ripple effect from that. That was a worm that takes advantage of a programming flaw that affects nearly all versions of the Microsoft Windows operating system.

There's nothing definitive on that front, John, just they're looking into any and all possibilities at this point to find out exactly what is causing this. The thing that's unusual, according to the officials that I've spoken to, is that there's this cascading effect. They said that there are blackouts.

They've seen blackouts before but nothing quite of this magnitude and it's the cascading effect that is curious and that is different and so that is what they're scrambling to find the root cause of.

KING: I want to tell our viewers what they're seeing as we continue this discussion. You saw moments ago the George Washington Bridge, a little before that the main bus terminals, the New York Port Authority, here from WCBS a street in New York City.

This one looks relatively calm at this hour, still daylight. A power outage across the city, the daylight of course making this a much easier situation to deal with, officials hoping to get the power back on as soon as possible.

Kelli, how from a procedural standpoint, how does the government react when they get wind of something like this not in one city but in two, three, and four? Is it any different in the post-September 11 environment as to how the government reacts?

ARENA: Very different because there is much more coordination in terms of any catastrophe whether it's terrorism or otherwise and, of course, I want to underscore no evidence that this is at all terrorist related.

You do have state and local law enforcement and homeland officials that can instantaneously reach each other. They all have liaisons and contacts that they deal with daily, information flow that is much better at this point than it was back on September 11 and so there is much more coordination than we have ever seen before.

There is, by the way John, somewhat of a security concern. We keep making the observation that it is daylight and so that does help the situation but once night falls if this situation is the same as it is right now there are some security concerns that law enforcement officials have expressed because back in the '70s when New York experienced a similar power outage there were big problems.

KING: Kelli Arena keeping track of the early stages of the investigations for us here in Washington. You're seeing a live picture from WCBS in New York. One can assume that more than anywhere else in this country the early reaction and fear of the people of New York was that this might be a terrorist attack.

Again, all information at this hour is that it is not. The federal government says, though it cannot say definitively just yet that that is the case while the investigations continue and as we keep track of them back to Kyra Phillips in Atlanta.

PHILLIPS: All right, John, thank you so much.

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